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101.
PurposeThe purpose of this study was twofold: (1) to examine the effects of School-Based Health Center (SBHC) use on academic outcomes for high school students, using a well-controlled, longitudinal model, and (2) to examine whether SBHC medical and mental health service use differentially impacts academic outcomes.MethodsAnalyses used a latent variable growth curve modeling approach to examine longitudinal outcomes over five school semesters for ninth grade SBHC users and nonusers from Fall 2005 to Fall 2007 (n = 2,306). Propensity score analysis was used to control for self-selection factors in the SBHC user and nonuser groups.ResultsResults indicated a significant increase in attendance for SBHC medical users compared to nonusers. Grade point average increases over time were observed for mental health users compared to nonusers. Discipline incidents were not found to be associated with SBHC use.ConclusionsSBHC use was associated with academic improvements over time for a high-risk group of users. The moderating effect of type of use (medical and mental health) reinforces the importance of looking at subgroups when determining the impact of SBHC use on outcomes.  相似文献   
102.
It is well known that the experimental dosimetry of brachytherapy sources presents a challenge. Depending on the particular-dosimeter used, measurements can suffer from poor spatial resolution (ion chambers), lack of 3D information (film) or errors due to the presence of the dosimeter itself distorting the radiation flux. To avoid these problems, we have investigated the dosimetry of a clinical 192Ir source using a polyacrylamide gel (PAG) dosimeter. Experimental measurements of dose versus radial distance from the centre of the source (cross-line plots) were compared with calculations produced with a Nucletron NPS planning system. Good agreement was found between the planning system and gel measurements in planes selected for analysis. Gel dosimeter measurements in a coronal plane through the phantom showed a mean difference between measured absorbed dose and calculated dose of 0.17 Gy with SD = 0.13 Gy. Spatially, the errors at the reference point remain within one image pixel (1.0 mm). The use of polymer gel dosimetry shows promise for brachytherapy applications, offering complete, three-dimensional dose information, good spatial resolution and small measurement errors. Measurements close to the source, however, are difficult, due to some of the limiting properties of the polyacrylamide gel.  相似文献   
103.
Cultures of differentiating fetal human type II cells have been available for many years. However, studies with differentiated adult human type II cells are limited. We used a published method for type II cell isolation and developed primary culture systems for maintenance of differentiated adult human alveolar epithelial cells for in vitro studies. Human type II cells cultured on Matrigel (basolateral access) or a mixture of Matrigel and rat tail collagen (apical access) in the presence of keratinocyte growth factor, isobutylmethylxanthine, 8-bromo-cyclicAMP, and dexamethasone (KIAD) expressed the differentiated type II cell phenotype as measured by the expression of surfactant protein (SP)-A, SP-B, SP-C, and fatty acid synthase and their morphologic appearance. These cells contain lamellar inclusion bodies and have apical microvilli. In both systems the cells appear well differentiated. In the apical access system, type II cell differentiation markers initially decreased and then recovered over 6 d in culture. Lipid synthesis was also increased by the addition of KIAD. In contrast, type II cells cultured on rat tail collagen (or tissue culture plastic) slowly lose their lamellar inclusions and expression of the surfactant proteins and increase the expression of type I cell markers. The expression of the phenotypes is regulated by the culture conditions and is, in part, reversible in vitro.  相似文献   
104.
Alport syndrome, hereditary glomerulonephritis with hearing loss, results from mutations in type IV collagen COL4A3, COL4A4, or COL4A5 genes. The mechanism for delayed glomerular disease onset is unknown. Comparative analysis of Alport mice and CD151 knockout mice revealed progressive accumulation of laminin 211 in the glomerular basement membrane. We show mesangial processes invading the capillary loops of both models as well as in human Alport glomeruli, as the likely source of this laminin. l-NAME salt–induced hypertension accelerated mesangial cell process invasion. Cultured mesangial cells showed reduced migratory potential when treated with either integrin-linked kinase inhibitor or Rac1 inhibitor, or by deletion of integrin α1. Treatment of Alport mice with Rac1 inhibitor or deletion of integrin α1 reduced mesangial cell process invasion of the glomerular capillary tuft. Laminin α2–deficient Alport mice show reduced mesangial process invasion, and cultured laminin α2–null cells showed reduced migratory potential, indicating a functional role for mesangial laminins in progression of Alport glomerular pathogenesis. Collectively, these findings predict a role for biomechanical insult in the induction of integrin α1β1–dependent Rac1-mediated mesangial cell process invasion of the glomerular capillary tuft as an initiation mechanism of Alport glomerular pathology.Alport syndrome is characterized by delayed-onset progressive glomerulonephritis associated with sensorineural hearing loss and retinal flecks.1 The most common form (80%) is X-linked and caused by mutations in the type IV collagen COL4A5 gene.2 The two autosomal forms of the disease account for the remaining 20% of Alport patients, and result from mutations in the COL4A3 and COL4A4 genes.3 The α3(IV), α4(IV), and α5(IV) proteins form a heterotrimer that is assembled into a subepithelial network in the glomerular basement membrane (GBM) that is physically and biochemically distinct from a subendothelial type IV collagen network comprising α1(IV) and α2(IV) heterotrimers.4 Mutations in any one of the three type IV collagen genes that cause Alport syndrome result in the absence of all three proteins in the GBM due to an obligatory association to form functional heterotrimers.5 Thus, the net result for all genetic forms of Alport syndrome is the absence of the α3(IV) α4(IV) α5(IV) subepithelial collagen network, resulting in a GBM type IV collagen network comprising only α1(IV) and α2(IV) heterotrimers.This change in basement membrane composition does not result in immediate pathology. The GBM appears to function adequately for the first few years of life and sometimes past the first decade.6 This delayed onset predicts a triggering mechanism for glomerular disease initiation and a theoretical window for therapeutic intervention that may arrest or significantly ameliorate Alport renal disease in its earliest stages. The activation of genes encoding GBM matrix molecules, matrix metalloproteinases (MMPs), and proinflammatory cytokines have all been linked to the progression of Alport glomerular disease. These, however, are events that occur after the onset of proteinuria, and therefore, downstream of disease initiation events.7–11 Consistent with this notion, experiments aimed at blocking these pathways have offered only limited therapeutic benefit in mouse models for Alport syndrome.8–10,12 One of the earliest events we have documented is the appearance of an irregular deposition of laminin 211 in the GBM of Alport mice,8 an observation confirmed in both Alport dogs and human patients with the disease.13 This laminin is normally found only in the mesangium of the glomerulus, and is not expressed in the GBM at any stage of embryonic development.14 Indeed, several other mesangial matrix proteins appear in the GBM of Alport mice, including laminin 111 and fibronectin.15,16In the Alport glomerulus, the podocytes are exposed to GBM that has an embryonic type IV collagen composition.17,18 This could result in altered cell signaling that may trigger the onset of the disease. It has been proposed that this type of mechanism may account for the reactivation of laminin 111 expression in podocytes,19 because laminin 111 is found in the GBM during development.14 Because the α1(IV)/α2(IV) collagen network contains significantly fewer interchain disulfide crosslinks,20 and the Alport GBM is thinner than normal,21 the Alport GBM is likely to be more elastic, resulting in elevated biomechanical strain on the glomerular cells at their points of contact with the GBM. Consistently, glomeruli from Alport mice have been shown to have elevated deformability relative to wild-type glomeruli,22 and salt-induced hypertension has been shown to accelerate glomerular disease progression in Alport mice.23In this work, we show that the cellular origin of GBM laminin 211 in Alport glomeruli is mesangial cell process invasion, and that deletion of laminin 211 in Alport mice ameliorates the mesangial process invasion of the glomerular capillary loops in Alport mice. Salt-mediated hypertension exacerbates this mesangial process invasion. A knockout mouse for the integrin α3β1 coreceptor CD151 also develops mesangial process invasion of the capillary loops with GBM deposition of laminin 211, demonstrating the same phenotype for a completely unrelated component of the capillary structural barrier. The CD151 knockout mouse model also shows accelerated glomerular disease progression in response to hypertension.24 We show that biomechanical stretching of cultured mesangial cells induces promigratory cytokines transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF), both known to be induced in Alport glomeruli.7,12 Inhibitor studies indicate that mesangial cell migration is mediated by integrin α1β1 signaling through the Rho GTPases RAC1 and CDC42. Consistently, integrin α1 deletion in Alport mice was previously shown to ameliorate glomerular disease progression and slow the accumulation of laminin 211 in Alport GBM.8 Here, we show that mesangial process invasion of the capillary loops is ameliorated in integrin α1–null Alport mice. These data define a role for biomechanical strain-mediated induction of mesangial cell process invasion as a key aspect of Alport glomerular disease initiation, and set the stage for defining novel therapeutic targets aimed at blocking this process.  相似文献   
105.

Background

Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.

Aim

This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.

Design and setting

Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.

Method

The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.

Results

The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.

Conclusion

The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care.  相似文献   
106.
Respiratory syncytial virus (RSV) is a recognised cause of lower respiratory tract infection in infants and young children. It causes severe respiratory disease in preterm infants with or without chronic lung disease. This study, conducted at Waterford Regional Hospital, evaluates the incidence of RSV infection in hospitalised children, its seasonal variation, and effectiveness of its prevention. Thirty eight percent of admitted children with bronchiolitis were RSV positive in the year 1999 November to March is the peak season for this infection. A highly selected group of 7 preterm children with or without chronic lung disease received Palivizumab prophylaxis. Not one of them acquired RSV infection. The high cost of Palivizumab was the main factor for its restricted use. Palivizumab was found to be effective in preventing RSV infection in our study. Since we had a small number of patients, further studies are needed for its economic and judicious use. Respiratory syncytial virus (RSV) is virulent easily transmissible and the most common cause of lower respiratory tract disease in children of less than 2 years of age. Up to 98% of children attending day care will be infected in single RSV season. Between 0.5% and 3.2% of children with RSV infection require Hospitalisation. Approximately 90,000 hospital admissions and 4500 deaths per year were reported in United States. In Ireland 2807 patients were admitted with Bronchiolitis in 1998. Major risk factors for hospitalisation due to RSV are Prematurity, chronic lung disease, congenital heart disease, compromised immunity and age younger then 6 weeks in otherwise healthy children. No effective treatment of RSV positive bronchiolitis beside supportive care in the form of adequate nutrition and oxygen therapy is available. Antiviral therapies such as Ribavirin has not been proved to be effective in RSV infection. Bronchodilators show variable results. Corticosteroids were not found effective. There is no effective vaccine available as yet. There is no proven method for active immunity. Various immunoglobulins are available for acquiring passive immunity against RSV infection. PREVENT study group in Jan. 1997 showed intravenous immunoglobulin (RSV- IGIV) use in reducing 41% to 63% hospitalisation in RSV patients. But RSV-IGIV was not licensed outside the United States because of risk of transmission of blood borne products, difficulty in administration ie. intravenous access, large fluid volume (15 ml/kg), high protein load (750 mg/kg), shortage of supply and need to postpone live vaccine (eg. MMR, varicella). monoclonal antibody Palivizumab was developed for prophylaxis against RSV infection. Clinical safety and efficacy of Palivizumab were demonstrated in IMpact trial published in Sept. 1998. Reduction in hospitalisation up to 55% was noted in this study. It was a pivotal randomised, double blind, placebo controlled phase 3 study conducted in 139 centres throughout Canada, United States and United Kingdom. We looked at our experience in patients admitted with bronchiolitis in Waterford Regional Hospital. We described the outcome of carefully selected Seven children of high risk group for Palivizumab prophylaxis. Its clinical Implications and cost effectiveness was evaluated in this study.  相似文献   
107.
The objective of this study was to determine whether the proposed Malan radiological sinusitis typing (RST) system facilitated a level of agreement and ease of use comparable with the Lund–Mackay (LM) system for chronic rhinosinusitis. Ten observers (one otolaryngologist and nine radiologists), in two separate centres (regional and tertiary), blinded to all clinical data, used these two systems to independently and randomly score and type 15 sets of scans, recording the time to score each film. Using unweighted kappa scores, both methods facilitated a moderate level of agreement, slightly better with the LM system. The Malan system is more time efficient. Preliminarily, this study shows that the Malan RST system is easy to apply with a comparable level of agreement. The Malan RST system is a focused attempt at classifying disease extent radiologically and correlating it to a surgical approach. It emphasizes that scoring systems are vulnerable and proves to be superior to the LM system as a surgical planning tool. To score sinus disease, a Quality‐of‐Life questionnaire in association with this typing method is more appropriate.  相似文献   
108.
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
109.
The Royal Marsden Hospital pilot tamoxifen chemoprevention trial   总被引:4,自引:0,他引:4  
A pilot randomised placebo controlled trial using tamoxifen in healthy women at increased risk of developing breast cancer, has been undertaken in order to evaluate the problems of accrual, acute symptomatic toxicity, compliance, and safety as a basis for subsequent large national multicentre trials designed to test whether tamoxifen can chemoprevent breast cancer.From October 1986 until June 1993, 2012 healthy women with an increased risk of developing breast cancer, usually because of a strong family history, were randomly allocated to receive tamoxifen 20 mgs/day or placebo for up to 8 years if possible.Accrual remained high in spite of extensive informed consent regarding potential risk. Acute symptomatic toxicity was low for participants on tamoxifen or placebo and compliance remained correspondingly high with a predicted 77% of women on tamoxifen and 82% of women on placebo continuing medication at 5 years. There was a significant increase in hot flushes (34% versus 20%) mostly in premenopausal women (p < 0.005), vaginal discharge (16% versus 4%, p < 0.005), and menstrual irregularities (14% versus 9%, p < 0.005). The requirements for hormone replacement therapy for women on tamoxifen or placebo were the same.Safety monitoring indicates no adverse anti oestrogenic effects of tamoxifen. There was no obvious effect of tamoxifen on bone mineral densities (single photon radial absorption). The fibrinogen and antithrombin III were both lowered, resulting in no observed detrimental effect on the ratio of these clotting factors. There was a significant reduction in the serum cholesterol maintained out to 5 years. Annual pelvic assessment using transvaginal ultrasound indicates an increased incidence of uterine fibromata and benign ovarian cysts. These results have encouraged the commencement of the NSABP national trial in the USA, and the subsequent start of national trials in Italy and the UK, which together should provide sufficient evidence to evaluate the efficacy of tamoxifen for prevention of breast cancer.  相似文献   
110.
Systemic candidiasis with renal involvement is a rare but well-recognized complication during intensive care treatment in very-low-birth-weight infants. We report a term neonate who developed anuria associated with bilateral bezoar formation in the renal pelvis and candidemia. The treatment consisted of placement of a nephrostomy tube in the left kidney, short-term irrigation with amphotericin B and iv, and later, oral administration of fluconazole.  相似文献   
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